1# Copyright 2016 Google Inc.
2#
3# Licensed under the Apache License, Version 2.0 (the "License");
4# you may not use this file except in compliance with the License.
5# You may obtain a copy of the License at
6#
7#      http://www.apache.org/licenses/LICENSE-2.0
8#
9# Unless required by applicable law or agreed to in writing, software
10# distributed under the License is distributed on an "AS IS" BASIS,
11# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12# See the License for the specific language governing permissions and
13# limitations under the License.
14
15import base64
16import json
17import os
18
19from cryptography.hazmat.primitives.asymmetric import ec
20import pytest
21
22from google.auth import _helpers
23from google.auth.crypt import base
24from google.auth.crypt import es256
25
26
27DATA_DIR = os.path.join(os.path.dirname(__file__), "..", "data")
28
29# To generate es256_privatekey.pem, es256_privatekey.pub, and
30# es256_public_cert.pem:
31#   $ openssl ecparam -genkey -name prime256v1 -noout -out es256_privatekey.pem
32#   $ openssl ec -in es256-private-key.pem -pubout -out es256-publickey.pem
33#   $ openssl req -new -x509 -key es256_privatekey.pem -out \
34#   >     es256_public_cert.pem
35
36with open(os.path.join(DATA_DIR, "es256_privatekey.pem"), "rb") as fh:
37    PRIVATE_KEY_BYTES = fh.read()
38    PKCS1_KEY_BYTES = PRIVATE_KEY_BYTES
39
40with open(os.path.join(DATA_DIR, "es256_publickey.pem"), "rb") as fh:
41    PUBLIC_KEY_BYTES = fh.read()
42
43with open(os.path.join(DATA_DIR, "es256_public_cert.pem"), "rb") as fh:
44    PUBLIC_CERT_BYTES = fh.read()
45
46SERVICE_ACCOUNT_JSON_FILE = os.path.join(DATA_DIR, "es256_service_account.json")
47
48with open(SERVICE_ACCOUNT_JSON_FILE, "r") as fh:
49    SERVICE_ACCOUNT_INFO = json.load(fh)
50
51
52class TestES256Verifier(object):
53    def test_verify_success(self):
54        to_sign = b"foo"
55        signer = es256.ES256Signer.from_string(PRIVATE_KEY_BYTES)
56        actual_signature = signer.sign(to_sign)
57
58        verifier = es256.ES256Verifier.from_string(PUBLIC_KEY_BYTES)
59        assert verifier.verify(to_sign, actual_signature)
60
61    def test_verify_unicode_success(self):
62        to_sign = u"foo"
63        signer = es256.ES256Signer.from_string(PRIVATE_KEY_BYTES)
64        actual_signature = signer.sign(to_sign)
65
66        verifier = es256.ES256Verifier.from_string(PUBLIC_KEY_BYTES)
67        assert verifier.verify(to_sign, actual_signature)
68
69    def test_verify_failure(self):
70        verifier = es256.ES256Verifier.from_string(PUBLIC_KEY_BYTES)
71        bad_signature1 = b""
72        assert not verifier.verify(b"foo", bad_signature1)
73        bad_signature2 = b"a"
74        assert not verifier.verify(b"foo", bad_signature2)
75
76    def test_verify_failure_with_wrong_raw_signature(self):
77        to_sign = b"foo"
78
79        # This signature has a wrong "r" value in the "(r,s)" raw signature.
80        wrong_signature = base64.urlsafe_b64decode(
81            b"m7oaRxUDeYqjZ8qiMwo0PZLTMZWKJLFQREpqce1StMIa_yXQQ-C5WgeIRHW7OqlYSDL0XbUrj_uAw9i-QhfOJQ=="
82        )
83
84        verifier = es256.ES256Verifier.from_string(PUBLIC_KEY_BYTES)
85        assert not verifier.verify(to_sign, wrong_signature)
86
87    def test_from_string_pub_key(self):
88        verifier = es256.ES256Verifier.from_string(PUBLIC_KEY_BYTES)
89        assert isinstance(verifier, es256.ES256Verifier)
90        assert isinstance(verifier._pubkey, ec.EllipticCurvePublicKey)
91
92    def test_from_string_pub_key_unicode(self):
93        public_key = _helpers.from_bytes(PUBLIC_KEY_BYTES)
94        verifier = es256.ES256Verifier.from_string(public_key)
95        assert isinstance(verifier, es256.ES256Verifier)
96        assert isinstance(verifier._pubkey, ec.EllipticCurvePublicKey)
97
98    def test_from_string_pub_cert(self):
99        verifier = es256.ES256Verifier.from_string(PUBLIC_CERT_BYTES)
100        assert isinstance(verifier, es256.ES256Verifier)
101        assert isinstance(verifier._pubkey, ec.EllipticCurvePublicKey)
102
103    def test_from_string_pub_cert_unicode(self):
104        public_cert = _helpers.from_bytes(PUBLIC_CERT_BYTES)
105        verifier = es256.ES256Verifier.from_string(public_cert)
106        assert isinstance(verifier, es256.ES256Verifier)
107        assert isinstance(verifier._pubkey, ec.EllipticCurvePublicKey)
108
109
110class TestES256Signer(object):
111    def test_from_string_pkcs1(self):
112        signer = es256.ES256Signer.from_string(PKCS1_KEY_BYTES)
113        assert isinstance(signer, es256.ES256Signer)
114        assert isinstance(signer._key, ec.EllipticCurvePrivateKey)
115
116    def test_from_string_pkcs1_unicode(self):
117        key_bytes = _helpers.from_bytes(PKCS1_KEY_BYTES)
118        signer = es256.ES256Signer.from_string(key_bytes)
119        assert isinstance(signer, es256.ES256Signer)
120        assert isinstance(signer._key, ec.EllipticCurvePrivateKey)
121
122    def test_from_string_bogus_key(self):
123        key_bytes = "bogus-key"
124        with pytest.raises(ValueError):
125            es256.ES256Signer.from_string(key_bytes)
126
127    def test_from_service_account_info(self):
128        signer = es256.ES256Signer.from_service_account_info(SERVICE_ACCOUNT_INFO)
129
130        assert signer.key_id == SERVICE_ACCOUNT_INFO[base._JSON_FILE_PRIVATE_KEY_ID]
131        assert isinstance(signer._key, ec.EllipticCurvePrivateKey)
132
133    def test_from_service_account_info_missing_key(self):
134        with pytest.raises(ValueError) as excinfo:
135            es256.ES256Signer.from_service_account_info({})
136
137        assert excinfo.match(base._JSON_FILE_PRIVATE_KEY)
138
139    def test_from_service_account_file(self):
140        signer = es256.ES256Signer.from_service_account_file(SERVICE_ACCOUNT_JSON_FILE)
141
142        assert signer.key_id == SERVICE_ACCOUNT_INFO[base._JSON_FILE_PRIVATE_KEY_ID]
143        assert isinstance(signer._key, ec.EllipticCurvePrivateKey)
144